<?php

require_once 'HTMLPurifier/Token.php';

/**
 * Defines a mutation of an obsolete tag into a valid tag.
 */
class HTMLPurifier_TagTransform
{
	
	/**
	 * Tag name to transform the tag to.
	 * @public
	 */
	var $transform_to;
	
	/**
	 * Transforms the obsolete tag into the valid tag.
	 * @param $tag Tag to be transformed.
	 * @param $config Mandatory HTMLPurifier_Config object
	 * @param $context Mandatory HTMLPurifier_Context object
	 */
	function transform($tag, $config, &$context) {
		trigger_error('Call to abstract function', E_USER_ERROR);
	}
	
	/**
	 * Prepends CSS properties to the style attribute, creating the
	 * attribute if it doesn't exist.
	 * @warning Copied over from AttrTransform, be sure to keep in sync
	 * @param $attr Attribute array to process (passed by reference)
	 * @param $css CSS to prepend
	 */
	function prependCSS(&$attr, $css) {
		$attr['style'] = isset($attr['style']) ? $attr['style'] : '';
		$attr['style'] = $css . $attr['style'];
	}
	
}

